Plumber Academy
by TheGamerHieikuYoko
Summary: Ben, Gwen and Kevin are off to Plumber Academy on the Moon. After arriving they make a huge discovery. Kevin has a half sister whose Powers are incredible if she only had the confidence to use them. Follow along with the team as they become full fledged Plumbers and face the road ahead.
1. Chapter 1

Ben 10 was now 16 and still played hero but he was lonely a lot because it seemed even though he was a hero girls didn't want to go out with him because he almost never had time for them. Today though he and his cousin Gwen Tennyson were entering Plumber Academy on the moon. The room was full of people hoping to get in Aliens of all races. But his eyes landed on the only two other humans in the room. Well, they looked human. He grabbed Gwen's arm and drug her over. The two weren't even standing near each other.

"Yo', Kevin." Ben called out, but his eyes were on the girl standing a few feet away. She had black and deep blue hair that was perfectly blended together making it look natural. She was model pretty with a great body to boot. what was she doing in a place like this? A fist to his head brought him back to his cousin and her boyfriend. "WHat?"

"You two are late." Kevin snapped. "I've been here for an hour."

"We missed our shuttle from Earth." Gwen sighed, kissing Kevin's cheek. "It wasn't Ben's fault this time so don't take it out on him."

Ben gave an annoyed smile that Kevin echoed. Ben's eyes slid off to the girl again. Black jeans and a black tank top both form fitting.

"She came in about half an hour ago." Kevin said. "No idea what she thinks she doing though. She doesn't look strong enough to be on active Plumber Duty."

"Neither do I." Gwen pointed out.

The girl suddenly looked up and around. She bit her lip looking a little scared. She walked to them.

"Excuse me." She was talking to Gwen. "May I hide behind your shield I cannot currently produce one myself."

"My shield?" Gwen wondered. "What am I shielding from?"

"Him." the girl nodded toward a guy's whose whole body was flame.

"He gonna attack or something?" Kevin asked. "In the middle of Plumber Academy?"

The girl didn't answer.

"The first round will be a powers round." Max Tennyson called to the room. "We will grade you on several things. You may use any and all powers at your disposal. Except for Ben." he looked at his grandson. "You know your restrictions, young man."

Ben huffed blowing his bangs out of his eyes. Gwen coughed into her hand and Kevin flat out laughed. Ben was restricted from using some of his most powerful, therefore best, aliens because they wanted the school to remain standing for more than a day. Ben looked at the girl.

"Hi, I'm Ben Tennyson, this is my cousin Gwen Tennyson and that's Kevin Levin..."

"Levin?" The girl looked at Kevin. She blinked at him with black eyes that matched his own. She then bowed to Kevin a little. "I'm Kelly. It's nice to meet you."

Ben was left anime crying while Gwen petted his back.

"What's your last name?" Kevin asked.

"I already told you." Kelly replied, blinking at them. "Levin. Just like yours."

Kevin wanted to hit something. He really wanted to hit something. This wasn't the girl's fault but he really wanted to hit something.

"Kevin Levin vs. ..." Kevin tuned out the rest. It was the fire guy. Everyone watched as Kevin slammed his hand into the wall and his entire body became made out of the same metal. He walked into the ring. "Begin."

"You might want to stand behind me after all." Gwen sighed as Ben had already moved behind Gwen flanking her. Kelly quickly echoed him on the other side. "Kevin, don't be stupid!"

It was too late Kevin had already made his arm into a mace and was swinging away hitting every time.

"Kevin, you're metal and he's fire!" Ben yelled.

The words didn't get through. Kevin was wailing on the guy who didn't seem to able to move.

Kelly watched her brother in awe.

"Oh, no watch out." She mumbled.

sure enough Kevin was blasted backwards as fire exploded from the opponent. Fire filled the room. Gwen's hands shot up and her shield appeared.

"Should I go Hero?" Ben asked, rubbing the back of his head.

"We aren't allowed to interfere." Gwen told him. "I could get points deducted just for summoning this shield."

"I'm just saying Overflow would be really good here." Ben replied.

"BEN!" Gwen yelled.

Ben huffed crossing his arms over his his chest he glanced at Kelly. Kevin had never mentioned a sister before. She was sure hot.

The Plumbers got everything cooled down to see Kevin was kneeling. He had ripped a power cable out of the floor and had it in his hands a shield of electricity was surrounding him. The Flame guy was down and out from using too much power.

"KEVIN!" Gwen and Ben bellowed, running to him.

Kevin looked at them his eyes unfocused but he let the shield down. Gwen and Ben pried his hands off of the cable. Ben suddenly jumped back left hand in the air out of Kevin's reach.

"Too close their, Kevin." He said, "You can't touch the watch and you know it."

Kevin nodded and let Gwen hoist him to his feet. Mindful of his watch Ben got Kevin's other side and they took him back to where Kelly was standing.

"Winner, Kevin Levin." Max declared, he turned to the Plumbers. "Someone get the doctor tell her the boy is half Osmosion."

A little amphibian guy ran off and returned with someone who looked human and drop dead gorgeous with very big breasts.

"I'm the Plumber doctor for this station." she told Ben and Gwen who were kneeling on either side of Kevin. "Half Osmosion half what please?"

"Human." Ben and Gwen chorused.

"Let me look him over then." She set a hand on Kevin's head and it began glowing. "This isn't his first time using energy..."

"Hardly." Ben deadpanned only to be hit on the head by Gwen.

"He didn't have choice." Gwen explained. "He's normally very careful after what happened last time..." she stopped for a moment. "But really, he usually only turns his body into various metals ..."

"Yes, I can see that."

"you can?" Gwen and Ben wondered.

"I am scanning his body my scan will also pick up uses of his powers." The Doctor laughed. She finally removed her hand. "He'll be fine."

"FINE?" Ben yelled. "last time he absorbed energy on that scale he tried to kill me!"

Kevin's hand shot up blindly and Gwen suddenly had Ben's left arm held above Ben's head. The Plumbers had all frozen. Kevin groped around then just fell on his side and went to sleep.

"Just let him rest." The doctor said, wondering about the girl's reaction to remove the boys left arm from being grabbed. "I'm able to remove or at least help control the side effects of Osmosion energy backlash." she looked at Kelly. "Much like you, young miss."

Kelly bowed her head and the woman bowed deeply. Then went to stand with the Plumbers.

"He just needs to sleep it off please adjust accordingly. "

"That was close." Gwen sighed in relief dropping Ben's arm. "I think he just wanted you to catch him. But, you know to be careful when he gets like this, Ben, don't let your guard down again."

Ben nodded rubbing the back of his head.

"It'll take at least ten days to fix the damage." someone reported to Max.

"Grandpa!" Ben was suddenly at Max's side. "I could fix it."

Max sighed he could practically see sparkles around Ben as he looked at him with pleading eyes. Gwen was standing over Kevin shaking her head in defeat.

"Fine, Ben but just this once." Max sighed, "Jurry Rigg is not to be used otherwise."

Ben opened his watch chose his alien and raised his hand. He felt an odd sensation in his mind and heard a voice.

_"Don't hit it so hard." _

So when he hit the watch he hit it with a lot less force. He turned into an Imp and set to work in a flash fixing what Kevin had broken in an attempt to live. When he was done he ended his transformation on his own and returned to Gwen whistling happily.

Ben and Gwen easily passed the test all the while Kelly waited keeping a close vigil over Kevin who had yet to wake up. Her fight was the last one and Kevin was finally awake. He sat up moaning and rubbing his head.

"I feel unusually sane." He said blinking up at Ben and Gwen then over to Kelly. "I should be outta my mind right now."

"...and Kelly Levin." Max called. Kelly walked into the ring facing an alien. "Begin."

Kelly stood there just stood there they guy charged her but suddenly grabbed his head and began screaming bloody murder.

"STOP!" he yelled clawing at his head. "MAKE IT STOP! STOP! NO! STOP! AHHHHHHHHHHH!"

The Plumbers all flinched.

"Winner, Kelly Levin."

Kelly returned to Kevin's group as the guy quit screaming and just sat on the mat rocking back and forth.

"What are you?" Gwen wondered.

"I'm half Osmosion/ half Ethereal." Kelly said, tucking hair behind her ear. "But I only have Ethereal powers like Telepathy. "

Ben started a bit. Telepathy? Was it her who'd told him not to hit the watch so hard? It had worked he'd gotten the alien he'd wanted so maybe he should take her advice to heart.

"Are you okay now, big brother?" Kelly wondered.

"Yeah, " Kevin nodded, rubbing his head. "Somehow, I'm fine. Though I don't think I can stand quiet yet."

"Now we'll call out the four with the lowest score and they will be shown to a shuttle that will take them home." Max called.

"They're eliminating this early?" Gwen wondered.

"They have to." Kelly answered. "Too many people showed up. They need to thin the herd."

"Makes since." Ben nodded.

Four people left one being the fire guy.

"Next, we'll be doing hand to hand combat." Max called.

"My specialty." Kevin smirked but didn't try to get up. "Just don't let me be first."

Gwen was first and quickly took out her opponent.

"I don't want to fight her." Kelly mumbled.

"Neither do we." Ben and Kevin agreed.

After what seemed like ever Kelly was put in the ring and showed that she had some hand to hand ability in fact by the looks of it she had a black belt in at least Judo or so Gwen was guessing. Kelly quickly returned to Kevin's side her hands clasped behind her. More and more fights before.

"Kevin Levin."

Kevin got up not feeling at full strength yet which he cursed. He could see that everyone could tell he wasn't at full strength but what they didn't know was he was smart and could read the flow of a fight easily. He used this to his advantage and won before going back to his group. Ben took down his guy rather easily as well. Gwen praised him and Kevin hit him on the back. Kelly just glanced at him then away. Kevin noticed.

Kevin lost interest in the fights and scanned the Plumbers that were watching over the tests and grading them he wondered which one was his and Kelly's dad. Some had their Plumber headgear on so he couldn't tell but he had the feeling the man was here watching them. He finally looked away as Kelly came back from her second round fight.

"Good job." He praised and rubbed his hand into her head. She blushed happily.

Ben, Gwen, Kevin and Kelly won their way to the semi finals. Ben and Gwen stood in the ring. There was a little white flag off to the side that they could use to surrender if they wanted no one had used it.

"Begin."

Ben picked up the flag and waved it shocking almost everyone in the room.

"I know what my cousin can do she taught me to fight." Ben explained. "I surrender."

Max nodded approving of Ben's choice.

"Kevin vs. Gwen." Max called.

Everyone watched Ben hand the flag off to Kevin as he left the ring.

"Begin."

Kevin waved the flag.

"Not a chance in hell." Kevin said, shaking his head.

Max nodded and wrote it down.

"Kelly vs. Gwen."

Kelly took the flag from Kevin as he left the ring and she entered.

"Begin."

Kelly waved the flag causing sweat drops from everyone.

"I'm sorry, but you scare me." Kelly explained.

She handed the flag to Max then ran back to Kevin.

"Winner Gwen Tennyson." Max declared.

Gwen left the ring looking very pleased with herself and rejoined her group. She had actually expected this was going to happen.

Four people were eliminated.

"Follow us to our next test." Max called.

Plumbers flanked the candidates as they walked through the halls.

"You never mentioned a sister." Ben said, with his arms behind his head.

"Didn't know I had one." Kevin replied. "She must be my half sister on dad's side."

"Yes, that's right." Kelly said, appearing at his side. "We have the same dad but different moms. I'm 16."

"Don't tell me that." Kevin sighed, "It's just going to piss me off."

"Kevin!" Gwen hissed.

Kevin sighed.

"Sorry." Kelly said softly.

"It's not your fault." Gwen assured her. "Really it's not is it, Kevin?"

"Naw." Kevin replied rubbing his hand into his sister's head again. "Not your fault in the least."

The Plumber walking against the wall at Kelly's side barely suppressed a flinch. No it was his fault and his son hated him for it. Though he was glad that Kevin seemed to be acknowledging his sister and even accepting her. He'd been worried about the two actually meeting for sometime now. He glanced over at them and felt a sudden urge to protect his daughter. That Ben Tennyson boy was trying to talk with her it wouldn't work she was too shy for that. Sure enough he wasn't making any progress.

They entered a room. In this room they had to assemble a blaster gun and fire at the target ten times. Ben was in the first group and hit the bullseye six out of ten times. He did the best in his group still he wasn't happy. Kevin was in the next group and hit the bullseye all ten as did Gwen in the group after that. Four more groups went then it was Kelly's turn.

"Uhm...I really apore the use of guns." She told Max.

"I'm sorry it's part of the test." Max said, gently. "Just do your best."

Kelly nodded and even though she hated guns had one assembled the fastest of all the groups and got a perfect score.

"I really hate guns." She sighed shaking her head.

Ben was crying rivers of tears into Gwen's shoulder. Kelly may hate guns but she'd gotten a better time and score than he had. She was cool too! She definitely his kind of girl.

Kelly returned to Kevin's side and got his praise. She ate it up.

Four were eliminated.

The tests continued all sorts of tests most that seemed to have no reason at all. They were finally doing written exams. Kelly sat with Ben on her left, Kevin on her right, and Gwen on Kevin's right scribbling answers on the tablet she'd been given. This is where she thrived book work and knowledge. She really didn't like fighting but had wanted to be a Plumber like her father and to meet her brother. She never looked up from her work.

" #350 you are eliminated."

They'd all been given test numbers at the start of the exam and the Plumbers had stated they should have done this earlier as it was easier. More and more were eliminated.

"Cheat much?" Ben scoffed, not looking up from his own test. "Where is the math portion of this thing?"

"I was wondering the same thing." Gwen sighed.

"Yeah." Kevin grunted.

Kelly was the first to finish her test and send it in. She then sat back in her chair.

"Math is the last test after the Science portion."

"UGH!" this was from Ben.

Ben knew he was doing well on the test but he also knew that Science, Technologies, and Math were going to be his saving grace for any areas he was lacking in. This test had everything in it and some he just wasn't familiar with so he had to hope he did well on those three. He smirked when he found out what the fifth to last test was.

"Strategy." Kevin wondered.

"I'm saved." Ben cried. "I'm saved. Oh, thank whatever Divine Being there is in this Universe."

Kelly giggled into her hand and Gwen snorted trying to suppress a laugh.

At the front of the room Max was smiling. Ben hadn't meant to say it so loud but the whole room had heard him. A cough from his side told him that Devin thought this was amusing as well.

Gwen sat back having finally finished that had been exhausting but Ben was right Strategy, Science, Technologies, and Math were probably going to be their saving graces on this test. There had been so much she was sure she'd scored high but she wasn't sure how high. She cast a worried look at Ben and Kevin both still working diligently. They had to be close to finished unless the translations section of the Languages test had slowed them down. She watched Ben scrunch up his face a childhood habit for when he was thinking his hardest and was worried. She heard Kevin muttering curses under his breath and worried more. They'd been promised that they could be a team if all of them passed Plumber Academy together. This was the one place where that dream could fall apart and they all knew it.

Kevin was suddenly working with vigor telling her that he'd gotten past the Translation section a few minuets later Ben was back as well. Through all of this Kelly just sat there staring ahead at the board.

Ben was the last of the group to finish his test. He wanted to cheer but didn't that Translation section had caught him off guard he wasn't Gwen after all. He could barely speak Spanish or French. He was sure that whole Language section was a failure. He glanced at Kelly he wanted to try talking to her again but his mental energy was drained and he just couldn't think of anything to say so he fell asleep with his head in his arms.

Gwen finally woke him up and he stretched his arms over his head.

"What's up is it over?" He asked.

"Yeah, we passed with top grades." Kevin informed. "Though Kelly got the best, then Gwen you and I tied for third."

"There's only about thirty of us left." Gwen noticed.

"I hope that nap got your brain working again." Kevin said, as they followed the instructors. "The next two tests are battle simulations."

"Bring it on." Ben grinned. "This is where we shine."

Gwen and Kevin both smiled. Kelly just followed obediently.

The four of them were put on team for the No Powers version of Battle Simulation.

"Choose your weapons." Max said.

Gwen, Ben and Kevin chose guns.

"Kelly?" Max asked.

They watched her sigh and hold her hand out. A sword with a crackling blue energy around it appeared in her hand.

"I'll use this." She replied. "Is it allowed."

"No, it's not." Devin spoke up for the first time. "That is part of your power. You must use Plumber issue weapons."

The sword vanished.

"If I must." Kelly sighed, picking up one of the guns. "May I take a sword too?"

"You can take whatever you think will be of use to you." Max answered.

The four entered the battle ground. It became obvious very quickly that Ben was the leader but he would take advice from the others he even switched to Kelly's tactics four times during the mission. They eventually won but Kevin had gotten hurt protecting Kelly while Gwen and Ben finished the fight.

Ben supported Kevin into the "Waiting Room". Kevin's left arm was hanging limp at his side. Gwen came in behind them arm around Kelly trying to console her.

"Well, I'm sure I don't need to tell you anything about what went wrong and how to improve." One the Magistrate said. "You're the best team we've seen today."

"Hey, enough." Ben said to Kelly as the female Doctor healed Kevin. "It was my fault okay? I'm used to making Strategies and Tactics for three not four. I didn't adjust fast enough. Kevin'll be fine he bounces back quickly enough."

Kelly nodded. Gwen sighed in relief Kelly had almost been in tears. She had to agree with Ben's assessment as well but figured she should add something.

"It was all of our faults." Gwen explained, calmly. "The three of us are used to working together and quickly fall into our old habits during battle we left you out to dry several times and on top of that ..."

"I'm not really much of a fighter." Kelly sighed with a nod.

"Not, that." Kevin hissed as his arm was healed. "You're a great fighter you just don't have the will to fight."

The Plumbers were nodding this team was obviously head and shoulders above the rest.

"We'll begin the Powers portion now."

"Yeah!" Ben cheered, fiddling with his watch. "Who should I choose?"

Gwen sighed in defeat and Kevin just smirked.

"Uhm...will we be on the same teams?" Kelly asked.

"Yes." Max replied.

"I'd like to try using my special ability." Kelly said, "I might not have the will to fight but I can lead my team to victory. May I?"

"You mean Overwatch?" Max clarified. Kelly nodded, Ben, Gwen and Kevin exchanged confused looks. "I was told it is a hard skill for you to use and could put a great amount of strain on you."

"If my team ends the fight in a certain amount of time I should be okay." Kelly said. "Please, It's really all I can do."

"Very well. You have permission to use Overwatch."

"I object!" Devin said, removing his helmet he saw recognition in Kevin's eyes. "Max, please reconsider that skill is dangerous."

"If Kelly feels she can do it we shouldn't hinder her." Max sighed. "You are not her father right now, Devin you're her instructor do I need to have you removed?"

Devin clenched his teach.

"No." he finally said.

He took Kevin, Gwen and Ben aside to explain what Overwatch did and beg them to be careful with her and what to look out for when she used it.


	2. Chapter 2

He took Kevin, Gwen and Ben aside to explain what Overwatch did and begged them to be careful with her and what to look out for when she used it.

* * *

"So how do we do this, little sister?" Kevin asked.

Kelly blinked up at him and gave him a small smile.

"I stay here." she explained, "I will be consumed in my energy and be able to see the whole battlefield and communicate with each of you telepathically to tell you where to move and what to do. I will be able to see any given situation all at once. It is a bit daunting, and it is draining. I have a time limit and we will have to finish within that limit or you will be on your own."

"If it comes to that we'll get ourselves out but what about you?" Ben wondered.

"I will be unable to move and will most likely pass out. I've only ever used this skill once during the siege of my home planet and that is what happened."

"Then one of us should stay here with you." Gwen countered.

"Yes, you will." Kelly told her. "You have the best offensive and defensive set here. You can be used as both ranged and close combat while still covering the middle field. You will protect me."

Kevin and Ben both relaxed and Gwen gave a stern nodded.

**Future Sight-1 **

Kelly was silent not wanting to acknowledge the screen. She glanced to where the Plumbers were talking about limiting Ben's powers all of their powers actually.

"It is within my abilities to do that." She informed them. They all looked at her.

"Kelly, no." Devin told her sternly. "That's enough. I know you want to help but your type of "limiting their powers" isn't the answer."

"I don't see why not." Kelly replied. "It would teach Ben and Kevin better control and help Gwen as well so she doesn't tire out so much. It will make them stronger in the long run even if it makes them weak right now. I've seen it, daddy, Azmuth will actually approve of my using this ability on Ben as he is ready to take the watch back."

"EH!" Ben cried, "I'll do it! Anything! Just don't let him take my Omnitrix!"

"I'm gain if'll teach me better control." Kevin shrugged.

"I could use help as well." Gwen informed. "While I am great in the ways Kelly pointed out my weakness is that I run low on Mana too fast and tire out faster. If Kelly's ability will help me to fix this I don't see a reason not to have her use it."

"Unless of course it will tire you out or put your life in danger." Kevin said quickly. "Then no way."

He got that small warm smile that he was coming to love from his sister.

"No it will not take anything out of me at all." Kelly said. "No bare with me this is going to sound weird."

"We're old friends with Weird." Ben deadpanned and lit up when he got that lovely musical giggle out of Kelly.

"Form Team." Kelly said, softly. She was sure that Kevin, Gwen, Devin, and Ben were the only one's who could hear her. "Name: Guardians of the Multiverse. Confirm." She looked at Gwen. "Think of a shield spell and attack spell that doesn't use a lot of mana." Gwen frowned but did as told. "Invite: Gwendolyn Tennyson." Gwen was shocked when a screen the same purple as her powers appeared in front of her she pressed yes. "Big Brother, think changing your body into metal and an energy attack."

"I don't use energy." Kevin said, shaking his head. "Too many bad experiences."

"You will be the first Osmosion who can use energy safely if we do this." Kelly informed.

"Hook me up then, little sister." Kevin smirked.

"Invite: Kevin E. Levin." Kevin's screen was black with green writing on it. He pushed yes. "Ben, think of the first Alien you ever turned into."

"That's easy." Ben said, "It was Heatblast."

"Invite: Benjamin Tennyson."

Ben's screen was Green with Black writing on it. He pressed yes.

"Welcome to my game." Kelly smiled. "To check your skills say 'Skills'."

They did.

"EH!" Ben cried loudly, and opened his watch everyone was looking at him. "EH!"

"Locked into Heatblast?" Kevin guessed.

"She's locked me into Heatblast with only Fireball! I can't even fly!" Ben cried.

"I did warn you." Kelly said, looking scared.

Ben calmed himself.

"No, no it's fine." Ben assured her. "Just a..." Gwen's scream echoed his own. "shock."

"Mana Shield and Mana Ball!" Gwen cried. "My spells! My precious spells!"

"I've got Energy Ball and Metal shift." Kevin shrugged calmly. "Can we win this with what we have?"

"Overwatch is infallible." Kelly informed. "Now for another shock you'll all be upset over...say Stats."

Sure enough the three teens were pissed and went through various forms of angry. When calm Kelly continued.

"The Inventory is where you can store things and only you will be able to get to them."

"What's this second tab here?" Gwen asked. "Oh, it a shared Inventory."

"That is new to me must be because we're on a team." Kelly informed.

She walked them through the rest of the functions then it was their turn.

* * *

Kelly's body was surrounded in blue light as she rose into the air arms out to either side but at a downward angle.

Ben hit his watch gently and transformed.

"Heatblast!" He called.

Kevin turned his body to metal.

Gwen stood on a hover board in front of Kelly as she was no longer able to fly. Her hands glowing purple.

_"You can teach yourselves other skills by practicing them repeatedly." _Kelly informed them Telepathically.

**Telepathy-1 **

She began guiding the boys into battle.


End file.
